When we make a choice, solve a problem, come to a decision, we can record the process in a single place. We can put here a list of our observations, to make sure we remember them when the time comes; we can include, too, our thoughts, our inferences, our potential lines of inquiry, things that intrigued us. But we can even take it a step further. Record what we ended up doing. Whether we had any doubts or reservations or considered other options (and in all cases, we’d do well to be specific and say what those were). And then, we can revisit each entry to write down how it went. Was I happy? Did I wish I’d done something differently? Is there anything that is clear to me in retrospect that wasn’t before?

…And then, when we’ve gathered a dozen (or more) entries or so, we can start to read back. In one sitting, we can look through it all. All of those thoughts on all of those unrelated issues, from beginning to end. Chances are that we’ll see…that we make the same habitual mistakes, that we think in the same habitual ways, that we’re prey to the same contextual cues over and over. And that we’ve never quite seen what those habitual patterns are…

Other great minds have suggested similar solutions for making better decisions.

Whenever you make a key decision or take a key action, write down what you expect will happen. Nine or 12 months later, compare the actual results with your expectations… Practiced consistently, this simple method will show you within a fairly short period of time, maybe two or three years, where your strengths lie—and this is the most important thing to know.

This might sound serious and formal. Might sound like homework.

But even when making decisions for our personal life, Harvard happiness expert Dan Gilbert reminds us we’re terrible at remembering what really makes us happy.

We overestimate how happy we will be on our birthdays, we underestimate how happy we will be on Monday mornings, and we make these mundane but erroneous predictions again and again, despite their regular disconfirmation.

You’ve never made the same dumb mistake twice in a row?

By building a checklist of what decisions do and do not work, you can create a system for yourself that doesn’t rely on a faulty memory and isn’t subject to impulsive emotions and short-term thinking. And checklists work.

What happens when you consistently use checklists across in an intensive care unit? People stop dying:

The proportion of patients who didn’t receive the recommended care dropped from seventy per cent to four per cent; the occurrence of pneumonias fell by a quarter; and twenty-one fewer patients died than in the previous year. The researchers found that simply having the doctors and nurses in the I.C.U. make their own checklists for what they thought should be done each day improved the consistency of care to the point that, within a few weeks, the average length of patient stay in intensive care dropped by half.

Sadly, life doesn’t come with an instruction manual custom designed for you.